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81.
Naoto Rikitomi Papa Salif Sow Kiwao Watanabe Duilio S. Nunez Glenda Martinez Tsuyoshi Nagatake 《Microbiology and immunology》1996,40(12):899-905
The susceptibility of 101 pneumococcal isolates from the respiratory tract during 1991–1994 was examined and compared with the susceptibility of isolates over the period of 1975–1990. A rapid increase of resistance was seen not only to penicillin but also other antimicrobial agents. During 1991–1994, 38% of all the isolates were resistant to penicillin. The rates of resistance during this period were 16–23% for three newer cephalosporins, 18% for imipenem, 69% for tetracycline, 31% for erythromycin, 20% for chloramphenicol and 9% for clindamycin. The use of antibiotics within one month prior to pneumococcal isolation was correlated with penicillin resistance (P < 0.05). Serotyping of the isolates by antiserum revealed differences in predominant types between penicillin-resistant (19F, 23F, 4) and -susceptible isolates (15, 4, 11A). Our data suggests that anti-pneumococcal antibiotics should be carefully chosen on the basis of susceptibility tests. 相似文献
82.
Mutans streptococci are considered the predominant pathogens in dental caries. Three methods, i.e. dot blot hybridization analysis, PCR analysis and SDS-blue dextran-PAGE, were examined for identifying mutans streptococcal species. In dot blot hybridization, DNA probe derived from the dextranase gene (dexA) of Streptococcus mutans hybridized with different intensities under the condition of low stringency against each species of mutans streptococci although the dexA probe was specific for S. mutans under the condition of high stringency. Oligonucleotide primers for polymerase chain reaction (PCR) were designed on the basis of the dexA DNA sequence. The primers amplified species-specific PCR products in the reference species (15 strains of 5 species) of mutans streptococci. An electrophoretic profile of dextranases from the mutans streptococci on SDS-blue dextran-PAGE also showed species-specific behavior. These results suggest that the three identification methods examined here are useful for distinguishing the species of mutans streptococci and also indicate that PCR analysis is suitable for simple, rapid and reliable identification of mutans streptococcal species. 相似文献
83.
Kazushige Morimoto Eisuke Tsuda Ahmed Abdu Said Eriko Uchida Satoshi Hatakeyama Masatsugu Ueda Takao Hayakawa 《Glycoconjugate journal》1996,13(6):1013-1020
Ten erythropoietin (EPO) fractions differing in sialic acid content, ranging from 9.5 to 13.8 mol mol–1 of EPO, were obtained from baby hamster kidney cell-derived recombinant human EPO by Mono Q column chromatography. The mean pI values of the EPO fractions determined by IEF-gel electrophoresis systematically shifted from 4.11 to 3.31, coinciding with the sialic acid content, without a change in the constitution of asialo N-linked oligosaccharides of each fraction. Although a linear relationship between thein vivo bioactivity and the sialic acid content of the fractionated, samples was observed until 12.1 mol mol–1 of EPO, there was no further increase in their activity over 12.4 mol mol–1 of EPO. On the other hand, an inverse relationship between thein vitro bioactivity and sialic acid content of EPO was observed. Also, we showed that thein vivo bioactivity of some fractions with low sialic acid contents was increased after treatment with 2,6-sialyltransferase, but thein vivo bioactivity of the other fractions with high sialic acid contents was either decreased or not affected.Abbreviations EPO
erythropoietin
- rHuEPO
recombinant human erythropoietin
- hCG
human chorionic gonadotropin
- BHK
baby hamster kidney
- CHO
Chinese hamster ovary
- NeuAc
N-acetyl neuraminic acid
- Gal
galactose
- HRCs
hemolyser-resistant cells
- WST-1
2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium Na
- IEF
isoelectric focusing
- pI
isoelectric point 相似文献
84.
The objective of this study was to determine whether exposure of plants to ozone (O3) increased the foliar levels of glucose, glucose sources, e.g., sucrose and starch, and glucose-6-phosphate (G6P), because in leaf cells, glucose is the precursor of the antioxidant, L-ascorbate, and glucose-6-phosphate is a source of NADPH needed to support antioxidant capacity. A further objective was to establish whether the response of increased levels of glucose, sucrose, starch and G6P in leaves could be correlated with a greater degree of plant tolerance to O3. Four commercially available Spinacia oleracea varieties were screened for tolerance or susceptibility to detrimental effects of O3 employing one 6.5 hour acute exposure to 25O nL O3 L-1 air during the light. One day after the termination of ozonation (29 d post emergence), leaves of the plants were monitored both for damage and for gas exchange characteristics. Cultivar Winter Bloomsdale (cv Winter) leaves were least damaged on a quantitative grading scale. The leaves of cv Nordic, the most susceptible, were approximately 2.5 times more damaged. Photosynthesis (Pn) rates in the ozonated mature leaves of cv Winter were 48.9% less, and in cv Nordic, 66.2% less than in comparable leaves of their non-ozonated controls. Stomatal conductance of leaves of ozonated plants was found not to be a factor in the lower Pn rates in the ozonated plants. At some time points in the light, leaves of ozonated cv Winter plants had significantly higher levels of glucose, sucrose, starch, G6P, G1P, pyruvate and malate than did leaves of ozonated cv Nordic plants. It was concluded that leaves of cv Winter displayed a higher tolerance to ozone mediated stress than those of cv Nordic, in part because they had higher levels of glucose and G6P that could be mobilized during diminished photosynthesis to generate antioxidants (e.g., ascorbate) and reductants (e.g., NADPH). Elevated levels of both pyruvate and malate in the leaves of ozonated cv Winter suggested an increased availability of respiratory substrates to support higher respiratory capacity needed for repair, growth, and maintenance.Abbreviations ADPG-PPiase
ADPglucose pyrophosphorylase
- ASC
L-ascorbic acid
- APX
ascorbate peroxidase
- Ce
CO2 concentration in air in the measuring cuvette during photosynthesis measurements
- Ci
CO2 concentration in the leaf intercellular spaces during photosynthesis measurement
- Chl
chlorophyll
- DHA
dehydroascorbic acid
- DHA reductase
dehydroascorbate reductase
- DHAP
dihydroxyacetone phosphate
- GAP
glyceraldehyde-3-phosphate
- Gluc
glucose
- GR
glutathione reductase
- Gsw
stomatal conductance with units as mmol H2O m-2 s-1
- GSSG
oxidized glutathione
- GSH
reduced glutathione
- G1P
glucose-1-phosphate
- G6P
glucose-6-phosphate
- G6P dehydrogenase
glucose-6-phosphate dehydrogenase
- 6PG
6-phosphogluconate
- 6PG dehydrogenase
6-phosphogluconate dehydrogenase
- F6P
fructose-6-phosphate
- FBP
fructose-1,6-bisphosphate
- MAL
malate
- MDHA reductase
monodehydroascorbate reductase
- PE
post-emergence
- PEP
phosphoenolpyruvate
- PGA
3-phosphoglycerate
- Pi
orthophosphate
- PYR
pyruvate
- Pn
net CO2 photoas-similation in leaves
- PPFD
photosynthetic photon flux density with units of mol photons m-2 s-1
- PPRC
pentose phosphate reductive cycle
- RuBP
ribulose-1,5-bisphosphate
- rubisco
ribulose-1,5-bisphosphate carboxylase/oxygenase
- SLW
specific leaf weight
- TCA cycle
tricarboxylic acid cycle
- Triose-P
DHAP+GAP 相似文献
85.
When prothalli ofAdiantum capillus-veneris L. were kept for 2 d in the dark, chloroplasts gathered along the anticlinal walls (Kagawa and Wada, 1994, J Plant Res 107: 389–398). In these dark-adapted prothallial cells, irradiation with a microbeam (10 gm in diameter) of red (R) or blue light (B) for 60 s moved the chloroplasts towards the irradiated locus during a subsequent dark period. Chloroplasts located less than 20 gm from the center of the R microbeam (18 J·m–2) moved towards the irradiated locus. The higher the fluence of the light, the greater the distance from which chloroplasts could be attracted. The B microbeam was less effective than the R microbeam. Chloroplasts started to move anytime up to 20 min after the R stimulus, but with the B microbeam the effect of the stimulus was usually apparent within 10 min after irradiation. The velocity of chloroplast migration was independent of light-fluence in both R and B and was about - 0.3 m·min–1 between 15 min and 30 min after irradiation. Whole-cell irradiation with far-red light immediately after R- and B-microbeam irradiations demonstrated that these responses were mediated by phytochrome and a blue-light-absorbing pigment, respectively. Sequential treatment with R and B microbeams, whose fluence rates were less than the threshold values when applied separately, resulted in an additive effect and induced chloroplast movement, strongly suggesting that signals from phytochrome and the blue-light-absorbing pigment could interact at some point before the induction of chloroplast movement.Abbreviations B
blue light
- FR
far-red light
- IR
infrared light
- R
red light 相似文献
86.
G. Thaller I. Hoeschele 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(7):1161-1166
A Bayesian approach to the statistical mapping of Quantitative Trait Loci (QTLs) using single markers was implemented via Markov Chain Monte Carlo (MCMC) algorithms for parameter estimation and hypothesis testing. Parameter estimators were marginal posterior means computed using a Gibbs sampler with data augmentation. Variables sampled included the augmented data (marker-QTL genotypes, polygenic effects), an indicator variable for linkage, and the parameters (allele frequency, QTL substitution effect, recombination rate, polygenic and residual variances). Several MCMC algorithms were derived for computing Bayesian tests of linkage, which consisted of the marginal posterior probability of linkage and the marginal likelihood of the QTL variance associated with the marker. 相似文献
87.
88.
Alec Breen Alan F. Rope Denise Taylor John C. Loper P. R. Sferra 《Journal of industrial microbiology & biotechnology》1995,14(1):10-16
Summary The use of DNA amplification fingerprinting (DAF) as a tool for monitoring mixed microbial populations in bioreactors was evaluated. Short (8-mer or 10-mer) oligonucleotides were used to prime DNA extracts from various biological reactors during polymerase chain reaction (PCR) amplification. The reactors examined in this study included two sets of anaerobic stirred tank continuous flow bioreactors. One set of anaerobic reactors was operated under methanogenic conditions and one set was operated under sulfate-reducing conditions. The anaerobic reactor communities in the methanol-fed reactors showed extensive DAF homology. DAF was also applied to a fixed-film azo dye degrading reactor to examine the degree of uniformity of colonization of the substratum in representative regions of the reactor. This method is a quick and relatively inexpensive means of monitoring microbial community structure during biological processes. Since no cultivation of the sample is involved, the genetic profile of the community is not biased by outgrowth conditions. DAF profiles may be useful for comparisons of population changes over time or of bench-scale vs pilot-scale reactors but not adequate for assessing community diversity. 相似文献
89.
二核苷酸重复多态性的非同位素检测及其在基因诊断中的应用 总被引:9,自引:1,他引:8
本文报道了一种检测二核苷酸重复多态性的简便的非同位素法,利用重复序列两侧的特异引物进行PCR扩增,产生的等位片段在薄层变性聚丙烯酰胺凝胶电泳上分离,再用灵敏的银染法显色。该方法不需要标记PCR产物,简便、快速,分辨率可达1bp,并可用多对引物同时进行多重PCR分析。用此方法对DMD家系成员dystrophin基因的5'-脑型外显子止游区和3'-非翻译区的两个(CA)。位点进行了扩增片段长度多态性分 相似文献
90.
用抗单纯疱疹病毒(HSV)型共同性gC和gD羊克隆抗体(McAb),包被即Eppendorf管,捕捉HSV,同时加入3个引物:一个是HSV─1/HSV─2型共同性上游引物,另两个分别是HSV─1和HSV─2型特异性下游引物。借此建立了能直接分型检测HSV的抗原捕获聚合酶链式反应(AC─PCR)。HSV─1的扩增产物为477bp,HSV─2的为399bp两型病毒经AC─PCR扩增后产生分子量不同的DNA片段,致使AC─PCR能直接分型检测HSV。HSV─1和HSV─2扩增产物的克隆和序列分析表明,本方法特异性好。用本法检测Balb/c幼鼠中枢神经系统HSV感染的脑标本,进一步证实本方法不仅敏感、特异,而且分型准确。 相似文献